检索结果-南通市图书馆

Peri-implant gas accumulation in response to magnesium-based musculoskeletal biomaterials:Reframing current evidence for preclinical research and clinical evaluation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Magnesium and Alloys 2024年第1期12卷 59-71页

作者： Yu Sun Heike Helmholz Regine Willumeit-Römer Institute of Metallic Biomaterials Helmholtz-Zentrum HereonMax-Planck-Str.1Geesthacht 21502Germany

Historically,the rapid degradation and massive gas release from magnesium(Mg)implants resulted in severe emphysema and mechanical *** the advent of new alloys and surface treatment methods,optimized Mg implants have re-entered clinics since last decade with reliable ***,the optimization aims at slowing down the degradation process,rather than exemption of the gas *** study involved a systematic evaluation of current preclinical and clinical evidence,regarding the physical signs,symptoms,radiological features,pathological findings and complications potentially associated with peri±implant gas accumulation(PIGA)after musculoskeletal Mg *** literature search identified 196 potentially relevant publications,and 51 papers were enrolled for further analysis,including 22 preclinical tests and 29 clinical studies published from 2005 to *** Mg-based materials have been evaluated in animal research,and the application of pure Mg and Mg alloys have been reported in clinical follow-ups involving multiple anatomical sites and musculoskeletal *** tissue and intraosseous PIGA are common in both animal tests and clinical follow-ups,and potentially associated with certain adverse *** examinations especially micro-CT and clinical CT scans provide valuable information for quantitative and longitudinal *** according to simulation tests involving Mg implantation and chemical processing,tissue fixation could lead to an increase in the volume of gas cavity,thus the results obtained from ex vivo imaging or histopathological evaluations should be interpreted with *** still lacks standardized procedures or consensus for both preclinical and clinical evaluation of ***,by providing focused insights into the topic,this evidence-based study will facilitate future animal tests and clinical evaluations,and support developing biocompatible Mg implants for the treatment of musculoskeletal

关键词： Magnesium implant Degradation Hydrogen Gas release Postoperative follow-up

On-the-fly precision spectroscopy with a dual-modulated tunable diode laser and Hz-level referencing to a cavity

在线全文

学校读者我要写书评

暂无评论

Advanced Photonics 2024年第4期6卷 36-44页

作者： Shuangyou Zhang Toby Bi Pascal Del’Haye max planck Institute for the Science of Light Friedrich-Alexander Universit?t Erlangen-Nürnberg Department of Physics

Advances in laser spectroscopy have enabled many scientific breakthroughs in physics, chemistry,biology, and astronomy. Optical frequency combs pushed measurement limits with ultrahigh-frequency accuracy and fast-measurement speed, while tunable-diode-laser spectroscopy is used in scenarios that require high power and continuous spectral coverage. Despite these advantages of tunable-diode-laser spectroscopy, it is challenging to precisely determine the instantaneous laser frequency because of fluctuations in the scan speed. Here, we demonstrate a simple spectroscopy scheme with a frequencymodulated diode laser that references the laser on-the-fly to a fiber cavity. The fiber cavity's free spectral range is on-the-fly calibrated with sub-10-Hz frequency precision. We achieve a relative precision of the laser frequency of 2 × 10-8for an 11-THz frequency range at a measurement speed of 1 THz∕s. This is an improvement of more than 2 orders of magnitude compared to existing diode-laser-spectroscopy *** scheme provides precise frequency calibration markers, while simultaneously tracking the instantaneous scan speed of the laser. We demonstrate the versatility of our method through various applications, including dispersion measurement of a fiber, ultrahigh-Q microresonators, and spectroscopy of a hydrogen fluoride gas cell. The simplicity, robustness, and low cost of this spectroscopy scheme are valuable for out-of-the-lab applications like lidar and environmental monitoring.

关键词： frequency comb gas spectroscopy integrated photonics radio-frequency modulation tunable laser spectroscopy

Steroidal scaffold decorations in Solanum alkaloid biosynthesis

在线全文

学校读者我要写书评

暂无评论

Molecular Plant 2024年第8期17卷 1236-1254页

作者： Rosalind Lucier Mohamed O.Kamileen Yoko Nakamura Sofiia Serediuk Ranjit Barbole Jens Wurlitzer Maritta Kunert Sarah Heinicke Sarah E.O'Connor Prashant D.Sonawane Department of Natural Product Biosynthesis Max Planck Institute for Chemical Ecology07745 JenaGermany Research Group Biosynthesis and NMR Max Planck Institute for Chemical Ecology07745 JenaGermany Biochemical Sciences Division CSIR-National Chemical LaboratoryPune 411008MaharashtraIndia

Steroidal glycoalkaloids(SGAs)are specialized metabolites produced by hundreds of Solanum species,including important vegetable crops such as tomato,potato,and *** it has been known that SGAs play important roles in defense in plants and“anti-nutritional"effects(e.g.,toxicity and bitterness)to humans,many of these molecules have documented anti-cancer,anti-microbial,antiinflammatory,anti-viral,and anti-pyretic *** these,α-solasonine andα-solamargine isolated from black nightshade(Solanum nigrum)are reported to have potent anti-tumor,anti-proliferative,and anti-inflammatory ***,α-solasonine andα-solamargine,along with the core steroidal aglycone solasodine,are the most widespread SGAs produced among the Solanum ***,it is still unknown how plants synthesize these bioactive steroidal *** comparative metabolomictranscriptome-guided approach,biosynthetic logic,combinatorial expression in Nicotiana benthamiana,and functional recombinant enzyme assays,here we report the discovery of 12 enzymes from *** that converts the starting cholesterol precursorto solasodine aglycone,and the downstreamα-solasonine,α-solamargine,and malonyl-solamargine SGA *** further identified six enzymes from cultivated eggplant that catalyze the production ofα-solasonine,α-solamargine,and malonyl-solamargine SGAs from solasodine aglycone via glycosylation and atypical malonylation *** work provides the gene tool box and platform for engineering the production of high-value,steroidal bioactive molecules inheterologoushosts usingsyntheticbiology.

关键词： steroidal glycoalkaloids Solanum biosynthetic pathway α-solamargine malonyl-solamargine specialized metabolites

From the unknown to spotlight:newly identified hormone adjusts hepatic cholesterol synthesis to dietary uptake

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第7期9卷 2845-2847页

作者： Yakum Bertrand Nkeh Resul Gökberk Elgin Gesine Saher Project Group Biology of Lipids Department of NeurogeneticsMax Planck Institute for Multidisciplinary SciencesGöttingenGermany

In a study published in Cell,Hu and colleagues discovered that the signaling activity of the intestinal hormone Cholesin leads to the attenuation of hepatic cholesterol synthesis in response to intestinal absorption thereby maintaining homeostatic levels of circulating cholesterol.1 These findings have major translational implications as they provide a potential new target for the management of hypercholesterolemia and associated disorders.

关键词： cholesterol hepatic synthesis

Influence of symmetric and asymmetric rolling on texture evolution of work-hardened AA 5xxx aluminium alloy

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Transactions of Nonferrous Metals Society of China 2024年

作者： Matja? Godec Stefan Zaefferer Jakob Kraner ?rtomir Donik Irena Paulin Institute of Metals and Technology max-planck-Institut für Eisenforschung， max-planck-Strasse 1 Impol 2000 d.d.， Partizanska cesta 38

The textures and microstructures of hot- and cold-rolled sheets of an AA 5454 aluminium alloy were studied， with special attention paid to comparing the texture development for the symmetric and asymmetric cold rolling. Scanning electron microscopy with electron-backscatter diffraction was used to monitor the development of the microstructure in the differently deformed and additionally annealed samples. Details of the formations and transformations of individual texture components occurring during the rolling processes were observed and discussed. The average grain sizes， textures and mechanical properties were correlated and explained for the symmetric and asymmetric cold-rolled samples. The asymmetric rolling is beneficial in terms of deep drawability because it reduces the planar anisotropy of the annealed material due to the decrease of the Cube， Goss， Rotated Cube and η- fibre texture components and the same time strengthens X1- and X2-fibre texture components which are shear texture components and improve deep drawability. During the asymmetric cold rolling， the temperature increases due to friction， triggering recrystallisation processes and leading to larger grains. It was also confirmed that asymmetric cold rolling uses less rolling force and consequently less energy to produce a final material with better formability， particularly earing.

关键词：

Is the speed of adjusting to environmental change condition dependent?An experiment with house mice(Mus musculus)

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Current Zoology 2024年第3期70卷 350-360页

作者： Karem Lopez-Hervas Neelam Porwal Mathilde Delacoux Alexandros Vezyrakis Anja Guenther RG Behavioural Ecology of Individual Differences Max Planck Institute for Evolutionary Biology24306 PlönGermany Department of Evolutionary Biology Faculty of BiologyAdam Mickiewicz UniversityWieniawskiego 161-712 PoznańPoland Department for Collective Behaviour Max Planck Institute of Animal Behaviour78464 ConstanceGermany centre for the Advanced Study of Collective Behaviour University of Konstanz78464 ConstanceGermany Animal Ecology Institute for Biochemistry and BiologyUniversity of Potsdam14469 PotsdamGermany

Environmental conditions change constantly either by anthropogenic perturbation or naturally across space and ***,a change in behavior is the frst response to changing *** fexibility can potentially improve an organism’s chances to survive and ***,we lack an understanding on the time-scale such behavioral adjustments need,how they actually affect reproduction and survival and whether behavioral adjustments are suffcient in keeping up with changing *** used house mice(Mus musculus)to test whether personality and life-history traits can adjust to an experimentally induced food-switch fexibly in adulthood or by intergenerational plasticity,that is,adjustments only becoming visible in the offspring *** lived in 6 experimental populations of semi-natural environments either on high or standard quality food for 4 *** showed previously that high-quality food induced better conditions and a less risk-prone ***,we tested whether the speed and/or magnitude of adjustment shows condition-dependency and whether adjustments incur ftness ***-history but not personality traits reacted fexibly to a food-switch,primarily by a direct reduction of reproduction and sloweddown *** whose parents received a food-switch developed a more active stress-coping personality and gained weight at a slower rate compared with their respective ***,the modulation of most traits was condition-dependent,with animals previously fed with high-quality food showing stronger *** study highlights that life-history and personality traits adjust at different speed toward environmental change,thus,highlighting the importance of the environment and the mode of response for evolutionary models.

关键词： animal personality context dependence environmental change Match-mismatch non-genetic inheritance phenotypic flexibility phenotypic plasticity

Discovery potential of the Glashow resonance in an air shower neutrino telescope

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2024年第8期48卷 266-275页

作者： Guo-Yuan Huang School of Mathematics and Physics China University of GeosciencesWuhan 430074China max-planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany

The in-ice or in-water Cherenkov neutrino telescope,such as IceCube,has already proved its power in measuring the Glashow resonance by searching for the bump around E_(ν)=6.3PeV arising from the W-boson *** are many proposals for the next few decades for observations of cosmic tau neutrinos with extensive air showers,also known as tau neutrino *** air shower telescope is,in principle,sensitive to the Glashow resonance via the channel W→τν_(τ)followed by the tau decay in the air(e.g.,TAMBO,which has a geometric area of approximately 500km^(2)).Using a thorough numerical analysis,we find that the discovery significance can be up to 90%with a TAMBO-like setup if PeV neutrinos primarily originate from neutron decays,considering the flux parameters measured by IceCube as the *** presence of new physics affecting the neutrino flavor composition can also increase the ***,if ultrahigh-energy neutrinos are dominantly produced from meson decays,it will be statistically difficult for an advanced proposal such as TAMBO to discriminate the Glashow resonance induced byν¯e from the intrinsicντ/ν¯_(τ)*** have identified several limitations for such advanced telescopes,in comparison with the in-ice or in-water telescope,when measuring resonances:(i)a suppressed branching ratio of 11%for the decay W→τν_(τ);(ii)the smearing effect and reduced acceptance because the daughter neutrino takes away(y)∼75%of the energy from the W decay;and(iii)a large attenuation effect for Earth-skimming neutrinos with the resonance.

关键词： Ultrahigh-energy neutrinos Neutrino telescopes Glashow resonance

在线全文

学校读者我要写书评

暂无评论

揭示大质量恒星团中高阶多星系统的起源

科学通报 2024年第26期69卷 3837-3839页

作者：李尚活 max planck Institute for Astronomy Heidelberg 69117Germany

大质量恒星在整个宇宙演化历史长河中起着重要的作用.它们贡献了整个宇宙环境中的绝大部分重元素和紫外辐射.大质量恒星可具有上百万倍的太阳光度,使得它们即使是在遥远的星系也依然可见.大质量恒星在形成和演化的过程中还通过高速星风... 详细信息

大质量恒星在整个宇宙演化历史长河中起着重要的作用.它们贡献了整个宇宙环境中的绝大部分重元素和紫外辐射.大质量恒星可具有上百万倍的太阳光度,使得它们即使是在遥远的星系也依然可见.大质量恒星在形成和演化的过程中还通过高速星风、大质量外向流、膨胀的HII区和超新星爆发等方式与其周围的星际介质发生相互作用,进而影响星系的轮廓、恒星及其行星系统的形成和演化.

关键词：超新星爆发星际介质宇宙演化太阳光度形成和演化 HII区紫外辐射行星系统

The current status and future development of high-temperature conventional superconductivity

在线全文

学校读者我要写书评

暂无评论

National Science Review 2024年第07期 18-20页

作者： Mikhail I.Eremets High Pressure Chemistry and Physics Group Max-Planck-Institut für Chemie

This survey highlights key advancements in high-temperature superconductivity in hydrogen-rich materials, emphasizing the robust evidence and reproducibility of superconductivity under challenging experimental conditions of megabar pressures. In the near future, achieving room-temperature superconductivity is highly probable, and the field is expected to transition towards near-ambient-pressure superconductivity.

关键词：